1. 26 9月, 2011 2 次提交
  2. 21 9月, 2011 1 次提交
    • R
      ARM: fix vmlinux.lds.S discarding sections · 6760b109
      Russell King 提交于
      We are seeing linker errors caused by sections being discarded, despite
      the linker script trying to keep them.  The result is (eg):
      
      `.exit.text' referenced in section `.alt.smp.init' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o
      `.exit.text' referenced in section `.alt.smp.init' of net/built-in.o: defined in discarded section `.exit.text' of net/built-in.o
      
      This is the relevent part of the linker script (reformatted to make it
      clearer):
      | SECTIONS
      | {
      | /*
      | * unwind exit sections must be discarded before the rest of the
      | * unwind sections get included.
      | */
      | /DISCARD/ : {
      | *(.ARM.exidx.exit.text)
      | *(.ARM.extab.exit.text)
      | }
      | ...
      | .exit.text : {
      | *(.exit.text)
      | *(.memexit.text)
      | }
      | ...
      | /DISCARD/ : {
      | *(.exit.text)
      | *(.memexit.text)
      | *(.exit.data)
      | *(.memexit.data)
      | *(.memexit.rodata)
      | *(.exitcall.exit)
      | *(.discard)
      | *(.discard.*)
      | }
      | }
      
      Now, this is what the linker manual says about discarded output sections:
      
      |    The special output section name `/DISCARD/' may be used to discard
      | input sections.  Any input sections which are assigned to an output
      | section named `/DISCARD/' are not included in the output file.
      
      No questions, no exceptions. It doesn't say "unless they are listed
      before the /DISCARD/ section." Now, this is what asn-generic/vmlinux.lds.S
      says:
      | /*
      |  * Default discarded sections.
      |  *
      |  * Some archs want to discard exit text/data at runtime rather than
      |  * link time due to cross-section references such as alt instructions,
      |  * bug table, eh_frame, etc. DISCARDS must be the last of output
      |  * section definitions so that such archs put those in earlier section
      |  * definitions.
      |  */
      
      And guess what - the list _always_ includes .exit.text etc.
      
      Now, what's actually happening is that the linker is reading the script,
      and it finds the first /DISCARD/ output section at the beginning of the
      script. It continues reading the script, and finds the 'DISCARD' macro
      at the end, which having been postprocessed results in another
      /DISCARD/ output section. As the linker already contains the earlier
      /DISCARD/ output section, it adds it to that existing section, so it
      effectively is placed at the start. This can be seen by using the -M
      option to ld:
      
      | Linker script and memory map
      |
      |                 0xc037c080                jiffies = jiffies_64
      |
      | /DISCARD/
      |  *(.ARM.exidx.exit.text)
      |  *(.ARM.extab.exit.text)
      |  *(.exit.text)
      |  *(.memexit.text)
      |  *(.exit.data)
      |  *(.memexit.data)
      |  *(.memexit.rodata)
      |  *(.exitcall.exit)
      |  *(.discard)
      |  *(.discard.*)
      |
      |                 0xc0008000                . = 0xc0008000
      |
      | .head.text      0xc0008000      0x1d0
      |                 0xc0008000                _text = .
      |  *(.head.text)
      |  .head.text     0xc0008000      0x1d0 arch/arm/kernel/head.o
      |                 0xc0008000                stext
      |
      | .text           0xc0008200   0x2d78d0
      |                 0xc0008200                _stext = .
      |                 0xc0008200                __exception_text_start = .
      |  *(.exception.text)
      |  .exception.text
      | ...
      
      As you can see, all the discarded sections are grouped together - and
      as a result of it being the first output section, they all appear before
      any other section.
      
      The result is that not only is the unwind information discarded (as
      intended), but also the .exit.text, despite us wanting to have the
      .exit.text preserved.
      
      We can't move the unwind information elsewhere, because it'll then be
      included even when we do actually discard the .exit.text (and similar)
      sections.
      
      So, work around this by avoiding the generic DISCARDS macro, and instead
      conditionalize the sections to be discarded ourselves.  This avoids the
      ambiguity in how the linker assigns input sections to output sections,
      making our script less dependent on undocumented linker behaviour.
      Reported-by: NRob Herring <robherring2@gmail.com>
      Tested-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
      Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
      6760b109
  3. 17 9月, 2011 2 次提交
  4. 16 9月, 2011 1 次提交
    • L
      asm alternatives: remove incorrect alignment notes · a7f934d4
      Linus Torvalds 提交于
      On x86-64, they were just wasteful: with the explicitly added (now
      unnecessary) padding, the size of the alternatives structure was 16
      bytes, and an alignment of 8 bytes didn't hurt much.
      
      However, it was still silly, since the natural size and alignment for
      the structure is actually just 12 bytes, 4-byte aligned since commit
      59e97e4d ("x86: Make alternative instruction pointers relative").
      So removing the padding, and removing the extra alignment is just a good
      idea.
      
      On x86-32, the alignment of 4 bytes was correct, but was incorrectly
      hardcoded as 8 bytes in <asm/alternative-asm.h>.  That header file had
      used to be an x86-64 only header file, but various unification efforts
      have made it be used for x86-32 too (ie the unification of rwlock and
      rwsem).
      
      That in turn caused x86-32 boot failures, because the extra alignment
      would result in random zero-filled words in the altinstructions section,
      causing oopses early at boot when doing alternative instruction
      replacement.
      
      So just remove all the alignment noise entirely.  It's wrong, and it's
      unnecessary.  The section itself is already properly aligned by the
      linker scripts, and all additions to the section had better be of the
      proper 12-byte format, keeping it aligned.  So if the align directive
      were to ever make a difference, that would be an indication of a serious
      bug to begin with.
      Reported-by: NWerner Landgraf <w.landgraf@ru.r>
      Acked-by: NAndrew Lutomirski <luto@mit.edu>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a7f934d4
  5. 15 9月, 2011 11 次提交
  6. 13 9月, 2011 1 次提交
    • D
      xen/e820: if there is no dom0_mem=, don't tweak extra_pages. · e3b73c4a
      David Vrabel 提交于
      The patch "xen: use maximum reservation to limit amount of usable RAM"
      (d312ae87) breaks machines that
      do not use 'dom0_mem=' argument with:
      
      reserve RAM buffer: 000000133f2e2000 - 000000133fffffff
      (XEN) mm.c:4976:d0 Global bit is set to kernel page fffff8117e
      (XEN) domain_crash_sync called from entry.S
      (XEN) Domain 0 (vcpu#0) crashed on cpu#0:
      ...
      
      The reason being that the last E820 entry is created using the
      'extra_pages' (which is based on how many pages have been freed).
      The mentioned git commit sets the initial value of 'extra_pages'
      using a hypercall which returns the number of pages (if dom0_mem
      has been used) or -1 otherwise. If the later we return with
      MAX_DOMAIN_PAGES as basis for calculation:
      
          return min(max_pages, MAX_DOMAIN_PAGES);
      
      and use it:
      
           extra_limit = xen_get_max_pages();
           if (extra_limit >= max_pfn)
                   extra_pages = extra_limit - max_pfn;
           else
                   extra_pages = 0;
      
      which means we end up with extra_pages = 128GB in PFNs (33554432)
      - 8GB in PFNs (2097152, on this specific box, can be larger or smaller),
      and then we add that value to the E820 making it:
      
        Xen: 00000000ff000000 - 0000000100000000 (reserved)
        Xen: 0000000100000000 - 000000133f2e2000 (usable)
      
      which is clearly wrong. It should look as so:
      
        Xen: 00000000ff000000 - 0000000100000000 (reserved)
        Xen: 0000000100000000 - 000000027fbda000 (usable)
      
      Naturally this problem does not present itself if dom0_mem=max:X
      is used.
      
      CC: stable@kernel.org
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      e3b73c4a
  7. 11 9月, 2011 3 次提交
  8. 10 9月, 2011 3 次提交
  9. 09 9月, 2011 1 次提交
  10. 07 9月, 2011 6 次提交
  11. 05 9月, 2011 2 次提交
    • J
      openrisc: don't use pt_regs in struct sigcontext · d7cb6667
      Jonas Bonn 提交于
      As it was decided not to export struct pt_regs to userspace, struct
      sigcontext shouldn't be using it either.  The pt_regs struct for OpenRISC
      is kernel internal and the layout of the registers may change in the
      future.  The struct user_regs_struct is what is guaranteed to remain
      stable, so struct sigcontext may use that instead.
      
      This patch removes the usage of struct pt_regs in struct sigcontext and
      makes according changes in signal.c to get the register layout right.
      
      The usp field is removed from the sigcontext structure as this information
      is already contained in the user_regs_struct.
      Signed-off-by: NJonas Bonn <jonas@southpole.se>
      Reviewed-by: NEmilio Cota <cota@braap.org>
      d7cb6667
    • P
      OMAP2430: hwmod: musb: add missing terminator to omap2430_usbhsotg_addrs[] · 10167873
      Paul Walmsley 提交于
      Add a missing array terminator to omap2430_usbhsotg_addrs[].  Without
      this terminator, the omap_hwmod resource building code runs off the
      end of the array, resulting in at least this error -- if not worse
      behavior:
      
      [    0.578002] musb-omap2430: failed to claim resource 4
      [    0.583465] omap_device: musb-omap2430: build failed (-16)
      [    0.589294] Could not build omap_device for musb-omap2430 usb_otg_hs
      
      This should have been part of commit
      78183f3f ("omap_hwmod: use a null
      structure record to terminate omap_hwmod_addr_space arrays") but was
      evidently missed.
      Signed-off-by: NPaul Walmsley <paul@pwsan.com>
      10167873
  12. 04 9月, 2011 1 次提交
  13. 02 9月, 2011 2 次提交
  14. 01 9月, 2011 1 次提交
    • D
      xen: use maximum reservation to limit amount of usable RAM · d312ae87
      David Vrabel 提交于
      Use the domain's maximum reservation to limit the amount of extra RAM
      for the memory balloon. This reduces the size of the pages tables and
      the amount of reserved low memory (which defaults to about 1/32 of the
      total RAM).
      
      On a system with 8 GiB of RAM with the domain limited to 1 GiB the
      kernel reports:
      
      Before:
      
      Memory: 627792k/4472000k available
      
      After:
      
      Memory: 549740k/11132224k available
      
      A increase of about 76 MiB (~1.5% of the unused 7 GiB).  The reserved
      low memory is also reduced from 253 MiB to 32 MiB.  The total
      additional usable RAM is 329 MiB.
      
      For dom0, this requires at patch to Xen ('x86: use 'dom0_mem' to limit
      the number of pages for dom0') (c/s 23790)
      
      CC: stable@kernel.org
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      d312ae87
  15. 31 8月, 2011 3 次提交
    • A
      x86, perf: Check that current->mm is alive before getting user callchain · 20afc60f
      Andrey Vagin 提交于
      An event may occur when an mm is already released.
      
      I added an event in dequeue_entity() and caught a panic with
      the following backtrace:
      
      [  434.421110] BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
      [  434.421258] IP: [<ffffffff810464ac>] __get_user_pages_fast+0x9c/0x120
      ...
      [  434.421258] Call Trace:
      [  434.421258]  [<ffffffff8101ae81>] copy_from_user_nmi+0x51/0xf0
      [  434.421258]  [<ffffffff8109a0d5>] ? sched_clock_local+0x25/0x90
      [  434.421258]  [<ffffffff8101b048>] perf_callchain_user+0x128/0x170
      [  434.421258]  [<ffffffff811154cd>] ? __perf_event_header__init_id+0xed/0x100
      [  434.421258]  [<ffffffff81116690>] perf_prepare_sample+0x200/0x280
      [  434.421258]  [<ffffffff81118da8>] __perf_event_overflow+0x1b8/0x290
      [  434.421258]  [<ffffffff81065240>] ? tg_shares_up+0x0/0x670
      [  434.421258]  [<ffffffff8104fe1a>] ? walk_tg_tree+0x6a/0xb0
      [  434.421258]  [<ffffffff81118f44>] perf_swevent_overflow+0xc4/0xf0
      [  434.421258]  [<ffffffff81119150>] do_perf_sw_event+0x1e0/0x250
      [  434.421258]  [<ffffffff81119204>] perf_tp_event+0x44/0x70
      [  434.421258]  [<ffffffff8105701f>] ftrace_profile_sched_block+0xdf/0x110
      [  434.421258]  [<ffffffff8106121d>] dequeue_entity+0x2ad/0x2d0
      [  434.421258]  [<ffffffff810614ec>] dequeue_task_fair+0x1c/0x60
      [  434.421258]  [<ffffffff8105818a>] dequeue_task+0x9a/0xb0
      [  434.421258]  [<ffffffff810581e2>] deactivate_task+0x42/0xe0
      [  434.421258]  [<ffffffff814bc019>] thread_return+0x191/0x808
      [  434.421258]  [<ffffffff81098a44>] ? switch_task_namespaces+0x24/0x60
      [  434.421258]  [<ffffffff8106f4c4>] do_exit+0x464/0x910
      [  434.421258]  [<ffffffff8106f9c8>] do_group_exit+0x58/0xd0
      [  434.421258]  [<ffffffff8106fa57>] sys_exit_group+0x17/0x20
      [  434.421258]  [<ffffffff8100b202>] system_call_fastpath+0x16/0x1b
      Signed-off-by: NAndrey Vagin <avagin@openvz.org>
      Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
      Cc: stable@kernel.org
      Link: http://lkml.kernel.org/r/1314693156-24131-1-git-send-email-avagin@openvz.orgSigned-off-by: NIngo Molnar <mingo@elte.hu>
      20afc60f
    • C
      powerpc/p1023rds: Fix the error of bank-width of nor flash · 0c81e4b4
      Chunhe Lan 提交于
      In the p1023rds, a physical bus of nor flash is 16 bits width.
      The bank-width is width (in bytes) of the bus width. So, the
      value of bank-width of nor flash is not one, and it should be
      two.
      Signed-off-by: NChunhe Lan <Chunhe.Lan@freescale.com>
      Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
      0c81e4b4
    • K
      powerpc/85xx: enable caam crypto driver by default · e09e2fb5
      Kim Phillips 提交于
      corenet based SoCs have SEC4 h/w, so enable the SEC4 driver,
      caam, and the algorithms it supports, and disable the
      SEC2/3 driver, talitos.
      Signed-off-by: NKim Phillips <kim.phillips@freescale.com>
      Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
      e09e2fb5